Instead of updating to A6.22 first, perhaps update to A6.40 instead.
free update A6.40.5 After that, update to A6.50.2. Again, make sure all 3D gamestudio programs are closed, all files and folders of your 3D gamestudio are set to
not write-only, double-click your key file to activate/unlock the demo, then after that use the downloaded updates,

(Granted you've got a legal version, and if you've got MSN, give me a PM and perhaps I can help you through 'remote-access' or the like)
Cheers